Reactive acrylic adhesives (sometimes called acrylates or reactive acrylics) are based on monomeric or oligomeric mixtures of the esters of acrylic or methacrylic acid. For simplicity, adhesives based on acrylate as well as those based on methacrylates are called acrylic adhesives.
The monomers are usually low-viscosity, colourless liquids of characteristic to pungent odour. Esters of higher alcohols and esters of diols do not have an appreciable odour.
Chemically, acrylates are Alpha, Betta unsaturated carbonyl compounds. They can react with nucleophiles ( at the Betta- carbon or directly at the carbonyl function) and with electrophiles( at the C=C double bond or at the non-bonding electrons on the oxygen). The C=C double bond(conjugated with the acid or ester function) is the most frequently used function for synthesising polymers. It can be readily converted into the polymer by a free-radical mechanism. In contrast to polyaddition, this reaction doesn’t require stoichiometric ratios of reactants.